By law, the US Department of Agriculture must review and update its dietary recommendations for the American public every five years. The most recent report of the Dietary Guidelines Advisory Committee was recently released and can be found here – http://www.cnpp.usda.gov/DGAs2010-DGACReport.htm

As you might expect, there are no big changes. The usual advice to reduce fat, increase grain products, etc etc is proffered.

What is of greater interest, however, is a recently published article that examines the DGAC report and offers a reasoned critique of its recommendations. The paper focusses on the quality of evidence that is used as the basis for the recommendations and what appear to be a lot of conflict and contradictions in that evidence, even though strong recommendations are issued anyway. It makes for interesting reading if you are not already familiar with some of the issues currently being debated. The paper is skillful in highlighting the internal contradictions in the report itself and gives you insight into just how shaky and inconsistent are the foundations for current nutritional advice.

In the face of contradictory evidence: Report of the Dietary Guidelines for Americans Committee by Adele Hite et al.

The paper can be found here: http://www.sciencedirect.com/science/journal/08999007

Here is my favourite part of the DGAC report: “Although adherence to the Dietary Guidelines is low among the US population, evidence is accumulating that selecting diets that comply with Guidelines reduces the risk of chronic disease and promotes health. Ultimately, individuals choose the types and amount of food they eat and the amount of physical activity they perform, but the current environment significantly enhances over-consumption of calories and discourages the expenditure of energy.”

Translation: “We think that people who stop eating the usual crappy American diet and follow our recommendations can improve their health, however, we are still working on the proof but nobody listens to us anyways. Therefore it is their fault they are fat and sick. Oh, and the environment we live in contributes to the problem, as well.”

After about 40 years of trying, if this was the correct prescription for our problems with obesity and chronic disease, you would think there would be, by now, irrefutable evidence that it works. After literally billions of dollars being thrown at this problem, we should be way beyond the “evidence is accumulating” stage of figuring out whether it works or not. That failure, along with a classic “blame the victim” and “blame the environment” approach, is what the DGAC report is founded on. I think Adele and her colleagues were far too polite in their critique. I shall tell her that over a glass of wine at the annual scientific meeting of  The Obesity Society this weekend in San Diego. I suspect that, privately, she may agree.